Thermostatically-operated device



Dec. 23, 1930. c. L. RAYFIELD 1,785,787-

THERMOSTATIGALLY OPERATED DEVICE Filed Sept. 15, 1927 Patented Dec. 23, 1930 UNITED STATES PATENT OFFICE CHARLES L. RAYFIELD, OF CHICAGO, ILLINOIS, ASSIGNOB '10 RAYFIELD MANUFAC- TUBING 00., OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS THERMOSTATICALLY-OPERATED DEVICE Application filed September 15, 1927. Serial No. 219,651.

The present invention relates to thermostatic operating mechanism, and more partic: ularly to a thermostatically operated flexible shaft.

An object of the present invention is to provide a novel thermostatic construction for imparting a rotaryfl-n'uOvement to a flexible shaft or the like.

Another object of the present invention is to provide means for connecting a clockspring-like thermostat to a flexible shaft in such a manner that the thermostat upon being actuated will impart arotary movement to the shaft.

Other objects and advantages of my invention will more fully appear from the following detailed description taken in connection with the accompanying drawing, which illustrates a single embodiment thereof and in which Figure 1 is a fragmentary elevation illustrating an application of my invention wherein the thermostat is disposed in a fur nace adjacent an'oil burner;

Figure 2 is a fragmentary elevation, partly in section and drawn to an enlarged scale, of

I the thermostat and its connection to the flexian end of theflex-ible shaft switch element.

' lar parts throughout the several views. The; numeral 10 designates generally a furnace ble shaft, as well as the connection between the shaft and a movable switch element;

Figure 3 is an enlarged sectional view of the clockspring-shaped thermostat taken on substantially the line TIL-III of Figure 2 looking in the direction indicated by the arrows;

Figure 4 is a sectional viewtaken on the line IVIV of Figure 3 and illustrating the mounting for the thermostat and the connection between thethermostat and an end ofthe flexible shaft, and

Figure 5- is an enlarged detailsectional View taken on substantially the line.V-V of Figure 2 illustrating the connection between v and a movable In the drawing:

Like reference characters designate simlwhich may be of the oil burner type and into which extends a burner nozzle 11. Posiby means 'of a bolt 13 to the lateral end 14 3, comprises a strip of metal bent into a spiral 5 shape resembling that of a clockspring.

This strip is preferably made of any conventional type of thermostatic metal.

One end of the thermostat 12 is anchored of an extension 15 secured to a tubular member or sleeve 16. Mounted upon the periphery of the sleeve 16 is a plate 17 which is adj ustably secured to the sleeve 16 by means of a setscrew 18. This plate 17 may be secured to the wall of the furnace through the means of thebolts 19.

Formed integral with plate 17 is a hub portion 18 disposed over and concentric with sleeve 16. The free end of the hub portion is positioned adjacent a slot 19' in the sleeve 16. This slot permits of air circulating through the sleeve to cool coil 12. Now obviously by adjusting the position of the plate 17 axially on tube 16, it is possible to move the hub portion 18 relative to slot 19 and thus vary the size of the opening afforded by slot 19 to the circulating air. Thisin turn results in the amount of air circulating through the sleeve being varied and thus de- 80 termines the degree to which the coil 12 will-= be cooled by the circulating air.

The other end of the thermostat 12 is bent into a circular shape 20 and is disposed about the periphery of a shaft 21. Disposed about the circular end 20 of the thermostatic strip is a split collar 22. The. thermostatic strip extends through the slit or slot 23 of this split sleeve or collar 22. The collar 22 is disposed on the threaded end of the shaft 21 and is ad justably secured thereto by means of asetthe other end of the collar abuts nut 27 thread- The shaft 21 extends through the bore of 9 I i the sleeve 16 and has its other end Provided with a reduced portion28 which is coupled to a flexible shaft 29 so that the two shafts 21 and 29 will rotate together. This flexible shaft 29 may be of any conventional construction and is preferably disposed inside of a flexible conduit 30, one end of which extends into the bore of the sleeve 16 and is fastened to the sleeve by means of a setscrew 31. r

The other end of the flexible shaft 29 extends into a switch housing 32 in which is disposed a switch designated generally by the reference character 33. The end of the conduit associated withthis end of the shaft has formed integral with it a tube 34 provided with a threaded portion 35 threaded into an extension 36 secured to the interior side of the casing wall. Also disposed about this end of the shaft 29 is a small piece of tubing 37 spaced from the end of the tube 34. The extreme end of the shaft 29, as shown in' Figure 2, is rotatably mounted in an extension or bracket 38 secured to the interior side of the casing wall. This shaft is held in place in the bracket by means of a pair of collars 39 and 40 which may be secured to the shaft by setscrews 41. v j

The portion of the shaft 29 disposed be: tween the end-s of the adjacent spacing tubes 34 and 37 has connected toit an insulation block 42 and a clamping plate 43. Each of these two members is provided with an arouate shaped groove 44'through which extends this portion of the shaft. The clamping plate 43 resiliently clamps theshaft 29'to the insulation block 42. through the means of'a spring urged bolt 45. The bolt extends through the block 42 and the plate 43 and has surrounding it a compression. spring 46 posi tioned between the plate 43 and a washer 47 held in place. by means of a nut 48 threaded on the end of the bolt. This spring 46 functions to at all times urge the plate 43 toward the block 42. Secured to the block 42 is a switch contact-53 (Figure 5)..cooperable withm contact 50. The two contacts 50 and 53 comprise parts of the switch 33. Secured to this contact 53 is an electrical conductor 54. The

contact 50 has a lateral extension 55 adapted upon rotation of the block 42 tostrike the contact 53 and thus establish an electricalconnection between the two'conductors; Nor- Q. mally this extension 55 abuts the lateral in- --.su1atin*1ag 56 secured to block 52.

Now it will be evident that when the thermostat 12' is exposed to a predetermined heat, it will expand andcause the shaft 21 to move 'in the direction'indicated by the arrow in Fig ure 3. This rotation of the-shaft results in the clamping plate 43 and the block 42 moving therewith until the lateral extension 55 of the these two members.

After an operation of the thermostat 12,

it Will, upon cooling and returning to its nor-.

mal position, move the block 42 and the clamping plate 43 back to their normal positions, thus breaking the connection between the two conductors 51 and 54.

Some of the principal advantages of the clockspring-like thermostat 12 are that it is relatively compact it is capable of a relatively great amount of movement uponeach operationwthereof, and it is adapted toflefli} ciently impart a rotary movement to a shaft or the like. Then,'too, it is simple to make and is economical to manufacture in. large quantities.

Another advantage of my compact coil thermostat is that all 'the turns of it are subjected to substantially the same degree of heat due'to thefact that they are disposed within each other and in substantially the of theready variation of the amount of air circulating through tube 16, thus enabling I to a certain extent, a controlof the atmospheric conditions surrounding the'coil 12.

Now, of course, I desire it understood that although I have illustrated and described in detail the preferred form of my invention,

the invention is not to be thus limited, but

only in so far as defined by the scope and spirit of the appended claims. I claim as my invention:

1. In a thermostatically operated device, the combination of a tubular member, a ro-- tary member extending through said tubular member, a thermostat coil having its outer .end secured to said tubular'member and its inner end secured to said rotary member, a support for said tubular member comprising a sleeve. in which said tubular member is axially shiftable, said tubular member having an air inlet for the entrance of air to circulate through said member and said thermostat coil, said sleeve adjusting the area of .said-Yair-inlet .hen said I y tubular member shifted in'saidsleeve. 2. Ina thermostatically operated device, the combination of a tubular member, a thermostat coil secured at its outer end to the inner end of said tubular member, a shaft extending through said tubular member and journalled at its outer end in the outer end of said tubular member, the inner end of said shaft being securedv to the inner end of said thermostat coil, said tubular mem ber having an inlet for the flow of air therethrough and through said thermostat coil, and a supporting sleeve receiving saidltubu lar mem er and cooperable therewith to control the area of said air inlet.

3. In a thermostatically operateddevicdf'lao the combination of a tubular member having an air inlet at its outer end and open at its inner end, a shaft journalled in the outer end of said tubular member and extending therethrough, a thermostat coil secured at its inner end to said shaft and secured at its outer end to said tubular member in the ath ofair flow through said tubular memer, said tubular member and sleeve being relatively movable to control the fiow of air through said tubular member,

4. In a thermostatically operated device,

the combination of a tubular member which.

is free to the flow of air therethrough, a shaft journaled in the outer end of said tubular member and extending axially therethrough, a thermostat coil adjacent to the outlet; end at said tubular member, said coil being secured at its outer end to said tubular member and at its inner end to said shaft, a sleeve receiving said tubular member, and an air inlet at the out'er end of said tubular member, said tubular member and sleeve being I relatively axially movable whereby to adjust the area of said air inlet and thereby the volume'of air flow through said tubular member.

' 5. In a thermostatically. operated device, the combination of 'a tubular member, a shaft journaled in the outer end of said tubular member, a thermostat coil adjacent the inner end of said member, the outer end of said coi being secured to said member, said coil at its inner end being secured to and supporting the inner end of said shaft, said tubular member being open to the flow of air therethrough and said coil being in the path of the air 'flowing from said member.

In testimony whereof I have hereunto subscribed my name at Chicago, Cook County, Illinois.

' CHARLES L. RAYFIELD. 

